Michelle's doctor recommended that she allow the miscarriage to occur without using medications that cause her uterus to contract, due to the cut that her emergency Cesarean for Josie created.

"I am resting and I have felt good physically, which is strange," says Michelle, who was 19 weeks and 1 day into her pregnancy when the miscarriage was diagnosed (the baby measured at 16 weeks).

After giving birth to oldest son Josh, Michelle and Jim Bob, 46, suffered her first miscarriage when Michelle got pregnant while taking oral birth control. She has previously said it was one of the reasons the couple no longer chooses birth control.

"We named that baby Caleb even though we didn't know if it was a boy or girl because that miscarriage was early," she says. "We will name this child and will know that we will see those children again someday in heaven."

Their daughter, Jill, 20, has been studying to become a midwife and had listened to the baby's heartbeat on Nov. 25, Michelle says. "She's been taking notes and keeping good track," says Michelle. "On Dec. 3, I felt a little uncomfortable but I thought it was just something I'd eaten. It could have been the beginning of something going wrong. I had my blood drawn yesterday, and it showed that my progesterone levels had dropped so something was not right [with the pregnancy]."

She says Jim Bob and the children are making sure she's resting. "The kids are mothering me now," she says. "Jill just brought me some food and they are taking good care of me."

After suffering the miscarriage of their 20th child, Jim Bob and Michelle Duggar will hold a memorial service on Wednesday, Dec. 14, for the baby girl they have named Jubilee Shalom Duggar.

The reality TV stars of TLC's 19 Kids and Counting had discovered on Thursday at a routine ultrasound appointment that their 20th child, due next April, no longer had a heartbeat. Advised by her doctor to let the miscarriage occur naturally, Michelle, 45, was being cared for at home by her family.

Following the miscarriage late Sunday night, Michelle began to feel lightheaded and as a precaution was taken to the hospital, where she was kept for observation, according to a family spokesperson. Michelle is recovering well and expected to return home later on Monday, the spokesperson adds.

"We have had many tears today," says Jim Bob Duggar, 46. "This is life, and I understand that we are going though something that many others have. You think about the what-ifs, but God gives us strength to go on. We won't be able to see this child's life and the phases that we've seen for our other children, but we know we will see this child in heaven one day. We are thankful for each child, and we are blessed to have the children we have here and the ones we will meet someday in heaven."

Jubilee Duggar's memorial service will be for friends and Duggar family members, who on late Sunday already held a private service in their home.

"We would like to thank everyone for their prayers, emails and outpouring of love," Jim Bob wrote in a letter he shared with PEOPLE. "As our whole family is grieving, we also know that God promises to work all things for good in our lives. Our prayer is that Jubilee's passing will help us all realize that this life is short, and our relationship with Jesus is the most important thing. He gives us a peace in our hearts as He guides us through whatever we might face."

Though the family is in mourning, Jim Bob says they are grateful for the health of youngest daughter, Josie, who turned 2 on Dec. 10. Josie survived against all odds after being born at just 25 weeks and 1 lb., 6 oz. and has developed normally with no lasting impairments.

"We were looking forward to this birthday because it is a milestone for her," he says. "It is wonderful that she is with us and doing so well."

On Wednesday, an unseasonably warm winter day in Springdale, Ark., friends and family of Jim Bob and Michelle Duggar gathered to pay their respects to the couple's 20th child, a stillborn baby girl named Jubilee Shalom.

"I feel a great sorrow and grief, and yet at the same time I have a peace in my heart," said Michelle. "This is so sad, but I have peace. There are people praying for us and angels surrounding our home, and there was peace in the sorrow and the grief. Those feelings are mingled together."

The reality stars of TLC's 19 Kids and Counting discovered on Dec. 8 at a routine doctor's appointment that their 20th child no longer had a heartbeat. Michelle, 45, miscarried the baby on Dec. 11, the day after their youngest child, Josie Brooklyn, born at 25 weeks gestation and just over 1 lb., turned 2 years old.

A letter Michelle recorded for Jubilee was played at the memorial. She wanted to "pour my heart out to Jubilee, and I knew there was no way I could read this at the service," she explains.

The Duggars also contacted the nonprofit organization Now I Lay Me Down To Sleep, which helps families deal with the miscarriage and loss of their babies, to take photos the family could keep and use at the memorial service. Some of those photos have been released without Jim Bob and Michelle's consent, according to a spokesperson for the family, and were intended for private use only.

The Duggars, devout Christians who have left the number of children they have "up to God," say they will now quietly spend time together with their family.

"We have so much to be thankful for," Michelle says. "I know that in the days and weeks to come there will be other things that I will walk though, and grief that will come, and there will be times that we will worship and sing praises. I know that God will allow me to continue to release the emotions that I will release."

Physically, Michelle says she has been resting and feels well.

Jim Bob added: "I really believe that God sees the bigger picture. I hope that her short life can encourage other people who have gone through things like this. It was very healing, and we have precious memories."